Rolling mills for wire, light section steel or medium section steel typically comprise a plurality of high quality installation components. A wire rolling train, with one or more lines, comprises a support grate for the rolling stock used mostly in the form of billets and a furnace where the billets are heated to rolling temperature. The billets are fed from the furnace to a break-down train comprising several rolling stands, permitting a twist-free rolling process. The stands in the break down train are equipped with load cells, measuring the roll separating force in order to better control rolling of difficult to shape high quality steels.
The intermediate train following the break-down train also comprises several rolling stands, for instance, of compact stands, which permit using roll barrels with high useful lives. A finishing train is located after the intermediate train, which can consist of a ten stand finishing block designed for maximum rolling speeds of up to 90 m/sec and above. Apart from the first two stands in the break-down train where box passes are used, the rolling stock is deformed exclusively in oval and round passes. The average reduction amounts, for instance, in the break-down train to approximately 24%, in the intermediate train to approximately 23%, in the finishing train to approximately 16%. The average reduction when rolling stock with a round diameter of, for instance, 5.5 mm from 120 mm, stock rolled to have a circular cross-section is wound into coils. The conveyance of the rolled stock coils from the reeling arrangement is performed onto a conveyance arrangement and, from there, on a hook conveyor, where the rolled stock is subjected to further cooling. Subsequently the rolled stock coils are shipped.
A wire reeling arrangement with a delivery device for a reeled-up rolled stock coil is described in DE 37 23 461 Al. The wire reeling arrangement has a coil shoulder lifting plate, which can be moved up and down by a central lifting rod in direction of the central axis of the reeling basket. The coil shoulder lifting plate lifts the rolled stock, wound into a coil to such an extent, that it can be moved out of the reeling basket.
In a particular arrangement, the rolled stock coil is shifted off the raised coil shoulder lifting plate of the reeling device by a kick-off arrangement in steps up to a coil conveyor belt. Several different arrangements are required for delivery and transfer of reeled coils from two reeling devices onto a coil conveyor belt. Thus, for instance, two pairs of kick-off devices for conveying the coils from the center of the reeling device to the center of the intermediate station, two pairs of kick-off devices for conveying the rings from the center of the intermediate station to the center of the coil conveyor belt, a lifting table in the region of the coil conveyor belt, a special plate coating in the region between the reel-up device and the coil conveyor belt so that the bottom windings of the coil will not be damaged during conveyance.
A disadvantage of kicking reeled coils onto a coil conveyor belt is that several separate devices are required (kickoff device, elevating tables or lifting tables, special plate coating). Also, damage to the surface of the bottom windings during the kickoff process caused by rough or damaged surfaces of the plate coating or through plate bulging because of temperature effects can occur in the conveyance region of the coils after an extended production period. Furthermore, individual windings or rod tips between the upper edge of the plate covering and the bottom edge of the kickoff device can jam especially in the case of thin round material. Since four kickoff devices intergrip during their movements, there exists also collision danger in case of faulty electrical control.
In another particular arrangement, the rolled stock coil is delivered from the raised lifting plate of the reel-up device in steps by walking beams and lifting or elevating tables onto a coil conveyor belt. For delivery and transfer of the wound coils from two reel-up devices onto one coil conveyor belt, several different arrangements are required. For instance, two walking beam conveyors, comprising a fixed grate and of mobile twin support arms for stepwise conveyance of the coils from the center of the reel-up device to the center of the fixed depositing grate. From there to the center of the lifting table, which simultaneously corresponds to the center of the coil conveyor belt. Thus, two lifting tables are required for accepting and depositing the reeled-up coils from the walking beam to the coil conveyor belt. The disadvantage of this known method is that, with two reel-up devices, four arrangements are required (two walking beam conveyors, consisting of mobile and fixed grates and two lifting tables). There exists further the danger of upsetting possibly production losses having to remove scrap because of repeated pickup and deposit of reeled coils. Several arrangements interrelated in a conveyance function constitute interfaces, which cannot always be closed by covering or deactivated by guide plates. Therefore, disturbances in the production sequence can occur. Furthermore, damage of rolled stock is possible. The reason for this is seen in relative motion of the bottom windings during contact with the conveyance arrangement caused by frequent pickup and deposit of the coils during the conveyance process. The plurality of conveyance arrangements disposed in the tightest space make maintenance more difficult resulting in increased costs.
Finally, in yet another arrangement, for delivery and conveyance of reeled-up coils from a reel-up device to a coil conveyor belt by means of walking beams, stationary pieces of roller track and a liftable and lowerable piece of roller track are used. Several different arrangements are required for delivery and transfer of the reeled-up coils from two reel-up devices onto one coil conveyor belt, namely two walking beam conveyors consisting of a fixed grate and movable twin support arms, for a stepwise conveyance of the coils from the center of the reel-up device to the center of the stationary piece of roller track. Furthermore, two stationary pieces of roller track with powered rollers for conveying the coils to the center of the liftable or raisable and lowerable piece of roller track is required. Additionally, a raisable and lowerable piece of roller track with powered rollers is required for acceptance and depositing of the reeled-up coils on the center of the coil conveyor belt. Herein, it is disadvantageous that several arrangements are required (two walking beam conveyors consisting of fixed and movable grates, two stationary pieces of roller track with powered rollers and one raisable and lowerable piece of roller track with powered rollers).
Because of the repeated pickup and depositing and because of the additional conveyance of the reeled-up coils, there exists the danger of upsetting the coils and possibly losses of production due to removal of scrap. Similar arrangements in conveyance interrelationships with each other from interfaces, which cannot always be closed by coverings or deactivated by guide plates. Interferences in the production sequence can therefore not be excluded. Since relative movement between the bottom windings and the conveyance rollers can occur, especially if the roller surfaces are damaged, additional surface damage of the rolled stock can occur during conveyance on roller tracks. With thicker round rolled stock, conveying problems can occur upon the roller tracks in that a rod tip located at the bottom of an already partially cooled coil hooks up at for instance a roller, a guide plate or a roller track frame.
An older solution for continuous deposition and conveyance of drawn wire is described in DE 1 294 907 Al. The wire coils falling off a drawing drum, one after the other, are diverted into a centering position by a deflection device attached to the drawing drum and are recaptured by a rotating receiving basket which comprises a disk-shaped base plate and a central core standing upright towards the top, around which the coils are dropped or fall. The basket is located on a table which is rotatably supported on low friction bearings upon the frame of a wheeled trolley. Such a depositing and conveyance arrangement for wire coils cannot be used in modern rolling mills with rolling speeds of 90 m/sec and because of other evident disadvantages.
A device for continuous formation of reeled-up wire coils and their conveyance is shown in DE 1 182 192 Al, wherein a rotary table for coil formation is disposed on a roller track. The wire coming from a suspended drawing block is wound upon a platform around an upright cylindrical core. The platform is conveyed upon the roller track to the rotary table. When the coil formation is terminated, the platform is conveyed from the rotary table to the portion of the roller track which continues the conveyance. This winding and conveying arrangement for wire coils cannot be used in rolling trains with the currently high rolling speeds and high throughputs.